1. Field of the Invention
The present invention relates to an image pickup apparatus, an image pickup method, and a non-transitory computer-readable medium storing a computer program for performing a pixel shift and depth combination to generate high-resolution combined image data having a large depth of field.
2. Description of the Related Art
There has been proposed a technique for combining a plurality of image data, which are acquired by performing a pixel shift with a movement amount that is a non-integer multiple of a pixel pitch, and generating high-resolution combined image data.
For example, Japanese Patent Application Laid-Open Publication No. H6-225317 describes a technique for shifting an image sensor of a Bayer array in a horizontal direction, a vertical direction, or an oblique direction by 0.5 pixel or one pixel at a time to perform photographing four or eight times and combining obtained four or eight images to thereby generate an image having double resolution in the horizontal direction and the vertical direction.
There has also been proposed a technique for performing focus bracket photographing for acquiring a plurality of images while changing a focus position and performing depth combination of the obtained plurality of images to thereby obtain an image having a large depth of field with an enlarged focus range.
For example, Japanese Patent No. 4678603 describes a technique for acquiring a plurality of images through focus bracket photographing, deforming the images such that feature points of the respective images coincide with one another, and selecting and combining pixels having the highest sharpnesses among pixels corresponding to one another among the plurality of images to output an omnifocal image focused on an entire screen.